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Heathkit SB-401 relay RL1 Aug 7th 2012, 22:09 3 2,121 on 9/8/12
Lightning Arrestors Jun 2nd 2012, 13:48 8 3,064 on 26/9/12

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Heathkit SB-401 relay RL1 KapAceHigh on 9/8/12
Thanks Zac for your reply.
Looking into this a bit further, there are two additional contacts (lugs) that are not connected. As you state, the mod may have been already made. So I am not going to attempt any changes unless I can come up ith the connection diagram for the relay. Also, it might not be possible without unsoldering a lot of the wires to this relay due to the high density of connections to it.



Heathkit SB-401 relay RL1 KapAceHigh on 7/8/12
I'm thinking of following a Heathkit recommendation to connect contact 7 of RL1 to ground to eliminate the problem of the transmitter remaining on transmit when I end transmission. This is due to "gassy" final tubes, the Heathkit bulletin states.

Maybe I'm missing something, but going through the schematics, I come up with six poles for RL1, not five. I do see a contact lug on the RL1 on my SB-401 without any connection. Can I assume this is number 7? Don't know if there are any other contacts without a connection. This could be possible.

Wonder if anyone has the connection diagram for RL1, or did the suggested fix.

Thanks all.

73's KC2ZDT

Lightning Arrestors KapAceHigh on 6/6/12
Thanks for the information and the importance of grounding everything.
Guess the best precaution is to disconnect the antenna and power from all the equipment ahead any approaching thunderstorm.

Lightning Arrestors KapAceHigh on 2/6/12
When I was WB2MHI from 1963 to 1968, the only type of coax lightning arrestor was the gap type, which I installed on my coax transmission line right ouside the entrance to the shack.

after about 42 years, I'm again a licensed ham,KC2ZDT, but still have vintage vacuum tube gear. My question is this: is a gas discharge tube type arrestor necessary with vintage tube equipment.
Bob K

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